Arteries bring oxygen-rich blood from heart to the rest of the body and veins return oxygen-poor blood back to heart. When leg veins cannot pump enough blood back to heart, will have chronic venous insufficiency (CVI).

CVI is also sometimes called chronic venous disease, or CVD. We have three kinds of veins: superficial veins, which lie close to the skin, deep veins, which lie in groups of muscles and perforating veins, which connect the superficial to the deep veins. Deep veins lead to the vena cava, our body′s largest vein, which runs directly to your heart.